A perspective on animal welfare of grazing ruminants and its relationship with sustainability

Sustainability is a complex theorem driven through the optimisation of interconnected economic, social and environmental parameters. Balancing trade-offs between these three parameters is used to define a sustainable system and whilst economic and, to a degree, environmental parameters can be numericized making optimisation more defined, social parameters are often more complex. In livestock systems animal welfare is held as a central pillar of sustainability but due to its complex nature, indicators of welfare are in practice often restricted to negative nutritional/environmental/health domains (e.g. poor food quality, injuries/diseases, behavioural expression restricted) rather than the wider more complex ‘behavioural’ domain indicators (e.g. expression of rewarding behaviours), let alone welfare-enhancing positive mental state experiences. This perspective piece discusses the potential synergies and trade-offs between animal welfare and economic, societal and environmental pillars of sustainability for grazing ruminant systems. Grazing is often considered more animal welfare friendly than housed or feedlot type systems, especially in relation to the behavioural and mental state domains (BMSD) within a more ‘natural’ environment since it may provide a positive experience to the animal. However, the welfare status of grazing ruminants can differ with factors such as management practices and environmental conditions greatly influencing nutritional/environmental/health domains (NEHD) of welfare, where a more ‘controlled environment’ can be efficacious. Animals that are not maintained at a good level of welfare will not express their productive potential, although improving welfare standards may lead to higher costs of production and therefore an economic break, as a critical component of sustainability, is often applied to what can be achieved on farm. However, there can also be win-wins which need to be sought out to realise true sustainability. For example, extending the grazing season can increase the economic performance of a farm as well as the BMSD of animal welfare by providing a positive experience to the animal, and products commercialised as ‘pasture-based’ can increase farm revenue through premiums associated to the consumers perception of ‘quality’. Larger operations can benefit from economies of scale and reduce environmental intensity, but expansion has also been seen as bringing welfare risks, especially in relation to the BMSD and the higher risk of negatively impacting behavioural interactions (e.g. frustration due to foraging drive being impeded). If animals can optimise their own efficiency of nutrient capture, there could be significant environmental benefits in allowing animals to select their own diets at grazing, i.e., promoting exploration and foraging (positive experiences). Increasing animal performance is seen as an effective approach to reducing emissions intensity, which has been borne out by the lower methane intensity of high-yielding dairy housed herds, although there are important ethical concerns regarding BMSD of animal welfare and the marked restriction in environmental choices and in foraging behaviour (negative effect on behavioural interactions). However, consumers need to understand that implementing more ‘natural’ production systems with higher animal welfare standards can incur extra costs for producers, leading to higher output prices and also higher emission’s per unit of product, which will require a reduction in consumption to reduce overall emissions. Development of integrated sustainability scorings is critically needed to jointly assess the three dimensions of sustainability, including animal welfare.